Mickey is about to take his psychology final, for which he has studied very hard. Just before the exam, the person sitting next to Mickey asks him the name of the physiologist who worked on classical conditioning. Mickey suddenly realizes that he cannot quite remember the name, but he knows that it starts with a P and is two syllables long. Mickey is experiencing .The tip-of-the-tongue phenomenon
The root-of-the-tongue phenomenonThe top-of-the-tongue phenomenonNone of the above

 The tip-of-the-tongue phenomenon

Explanation:

The tip-of-the-tongue phenomenon is the mechanism in which a person has the tendency to have knowledge or answer to any particular subject but is not able to produce words from memory.

According to the question, Mickey is facing tip-of-the-tongue phenomenon as he is confident that he knows physiologists name but is not able to completely recall the name except for initial word and syllable in it.    

Other options are incorrect because root of the tongue mechanism and top of the tongue mechanism is not experienced by Mickey .Thus, the correct option is tip-of-the-tongue phenomenon.

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